Characterization of the yeast population in olive brines

Yeasts were isolated from spontaneous fermentations of olives in brines. Ascomycetous species dominated the yeast flora (>90%) and among them Pichia membranae-faciens and related species. Some components of the olives were tested as substrates for growth. Killer activity was observed in approximately half of the isolates, and the wider spectra were displayed by strains of Pichia anomala .     

Determination of the phytotoxicity of barium in leach-field disposal of gas well brines

Summary A study was conducted to determine the effect of barium on yield and elemental composition of plants growing near natural gas wells. Brines containing potentially phytotoxic concentrations of barium are periodically released into leach-fields at these wells. Data on plant yield, soil and plant Ba, Ca, Mg, Na, and K concentrations, and soil pH were collected from high-barium well sites, and from greenhouse experiments using simulated brines. Barium had no detectable effect upon plant yield, and contributed only to variations in its own concentration in plants studied. Barium also exhibited biodiminution, in contrast to all other elements studied. Sodium was implicated at the major cause of phytotoxicity at gas well leach-fields. Due to interference of potassium uptake by soidum, the soil sodium/potassium ratio was found to be closely correlated with plant yield fluctuations.     

Modelled and measured dynamics of viruses in Arctic winter sea-ice brines

We describe a model based on diffusion theory and the temperature-dependent mechanism of brine concentration in sea ice to argue that, if viruses partition with bacteria into sea-ice brine inclusions, contact rates between the two can be higher in winter sea ice than in seawater, increasing the probability of infection and possible virus production. To examine this hypothesis, we determined viral and bacterial concentrations in select winter sea-ice horizons using epifluorescence microscopy. Viral concentrations ranged from 1.6 to 82 x 10(6) ml(-1) of brine volume of the ice, with highest values in brines from coldest (-24 to -31 degrees C) ice horizons. Calculated virus-bacteria contact rates in underlying -1 degrees C seawater were similar to those in brines of -11 degrees C ice but up to 600 times lower than those in ice brines at or below -24 degrees C. We then incubated native bacterial and viral assemblages from winter sea ice for 8 days in brine at a temperature (-12 degrees C) and salinity ( approximately 160 psu) near expected in situ values, monitoring their concentrations microscopically. While different cores yielded different results, consistent with known spatial heterogeneity in sea ice, these experiments provided unambiguous evidence for viral persistence and production, as well as for bacterial growth, in -12 degrees C brine.     

Effect of salt on the killer phenotype of yeasts from olive brines.

The killer properties of yeasts isolated from olive brines were examined in the absence and presence of sodium chloride in concentrations of up to 6% (wt/vol). An apparent enhancement of the killing action as the salt concentration increased, as well as changes in the spectra of activity against selected target strains, was observed in a few strains. Culture filtrates from killer strains grown at different NaCl concentrations (0, 3, or 6% [wt/vol]) were tested against sensitive yeasts cultivated under the same conditions. While the sensitivity of the target strain greatly increased in the presence of salt, no significant effect on toxin production was noticed.     

Microbial inhibition by an isolate of pediococcus from cucumber brines

We reported earlier that Pediococcus cerevisiae FBB-61 inhibited Lactobacillus plantarum FBB-67 in mixed species inoculation used for the fermentation of brined cucumbers. Herein, 16 isolates of the Pediococcus genus from various sources were tested for inhibitory activity against L. plantarum and other microorganisms by a seeded-agar screening technique. Only two of the 16 isolates gave consistent and distinctive zones of inhibition, and both were isolated from fermenting cucumber brines on separate occasions. These two isolates did not inhibit each other but did inhibit the other 14 Pediococcus isolates in addition to L. plantarum. They also inhibited several other gram-positive bacteria, but not four species each of gram-negative bacteria and yeasts tested. Inoculation of cucumber juice broth with P. cerevisiae FBB-61 and L. plantarum WSO resulted in a drastic reduction in the plate count of L. plantarum WSO during day 1, but counts increased rapidly thereafter. Consequently, acid production by L. plantarum WSO was delayed. Noninhibitory isolates of Pediococcus had no appreciable effect on growth and acid production by L. plantarum WSO.     

Diatoms in a peatbog polluted with oil-field brines in the Kolva River basin,Komi Republic

The first data about the diatoms of phytobenthos and epiphyton in water biotopes of a peatbog in the Kolva River basin (a tributary of the Pechora River) polluted by oil-field brines are reported. As a total, 49 species with varieties and forms from 14 genera and 9 families have been found. Dominating complexes of communities with halophilic diatoms have been revealed. The ecology of the species resistant to mineral pollution is discussed.     

An ecological study of lactic acid bacteria from Almagro eggplant fermentation brines

AIM: Identification of the predominant lactic acid bacteria (LAB) involved in spontaneous fermentations of Almagro eggplants, and evaluation of the biodiversity by molecular typing. METHODS AND RESULTS: Almagro eggplant fermentations in three factories (A, B and C) enjoying Protected Designation of Origin (PDO) status were monitored by chemical and microbiological analysis of brines. LAB isolates from brines were identified by phenotypic analysis and by species-specific PCR reactions and typed by randomly amplified polymorphic DNA (RAPD)-PCR. All isolates from factories A and C belonged to the genus Lactobacillus (Lact.), whereas isolates from factory B belonged to Lactobacillus (50%), Leuconostoc (Ln.) (25%) and Lactococcus (Lc.) (25%); 1.9% of this microbiota was considered cosmopolitan. The genera Leuconostoc and Lactococcus and the species Lact. acidophilus and Lact. paracasei had never previously been reported in Almagro eggplant fermentations. CONCLUSION: Considerable differences in the composition of the lactic acid microbiota participating in the Almagro eggplant fermentations exist. Brine NaCl concentration has a notable influence both in number and in the species participating. SIGNIFICANCE AND IMPACT OF THE STUDY: The original aspect of this work consists of an ecological study of the LAB taking part in spontaneous Almagro eggplant fermentations from different factories. Participation of Leuconostoc and Lactococcus species and of Lact. acidophilus and Lact. paracasei, which had never before been described for this pickle, and the evidence that a lactic fermentation does not always take place, were the most relevant results.     

Hydrogenotrophic denitrification and perchlorate reduction in ion exchange brines using membrane biofilm reactors

Halophilic (salt loving), hydrogenotrophic (H₂ oxidizing) denitrifying bacteria were investigated for treatment of nitrate <$>({\rm NO}_3^ ‐ )<$> and perchlorate <$>({\rm ClO}_4^ ‐ )<$> contaminated groundwater and ion exchange (IX) brines. Hydrogenotrophic denitrifying bacteria were enriched from a denitrifying wastewater seed under both halophilc and non‐halophilc conditions. The cultures were inoculated into bench‐scale membrane biofilm reactors (MBfRs) with an “outside in” configuration, with contaminated water supplied to the lumen of the membranes and H₂ supplied to the shell. Abiotic mass transfer tests showed that H₂ mass transfer coefficients were lower in brines than in tap water at highest Reynolds number, possibly due to increased transport of salts and decreased H₂ solubility at the membrane/liquid interface. An average <$>{\rm NO}_3^ ‐ <$> removal efficiency of 93% was observed for the MBfR operated in continuous flow mode with synthetic contaminated groundwater. Removal efficiencies of 30% for <$>{\rm NO}_3^ ‐ <$> and 42% for <$>{\rm ClO}_4^ ‐ <$> were observed for the MBfR operated with synthetic IX brine in batch operating mode with a reaction time of 53 h. Phylogenetic analysis focused on the active microbial community and revealed that halotolerant, <$>{\rm NO}_3^ ‐ <$> ‐reducing bacteria of the bacterial classes Gamma‐Proteobacteria and Sphingobacteria were the metabolically dominant members within the stabilized biofilm. This study shows that, despite decreased H₂ transfer under high salt conditions, hydrogenotrophic biological reduction may be successfully used for the treatment of <$>{\rm NO}_3^ ‐ <$> and <$>{\rm ClO}_4^ ‐ <$> in a MBfR. Biotechnol. Bioeng. 2009; 104: 483–491 © 2009 Wiley Periodicals, Inc.     

Flexistipes sinusarabici,a novel genus and species of eubacteria occurring in the Atlantis II Deep brines of the Red Sea

Four isolates of a gram-negative flexible bacterium have been obtained from brine water samples of the Atlantis II Deep of the Red Sea at a depth of 2000 m. One isolate (MAS 10) was studied in detail. Cells are nonmotile, flexible rods, measuring about 0.3 m in width and 5 to 50 m in length. The new organisms are heterotrophs growing anaerobically on yeast extract, meat extract, peptone, tryptone, and, less efficiently, on acetate and casamino acids. Growth occurs between 30% and 53°C at pH 6 to 8 in the presence of at least 3% NaCl. The shortest doubling time is 8.5 h under optimal growth conditions. Cells are sensitive to the antibiotics penicillin, ampicillin, vancomycin, and streptomycin, but resistant to tetracyclin and rifamipicin. The GC-content of the DNA is 39 mol%. Based on their 16S rRNA the new isolates group with the general cluster of eubacterial phyla. Since they show no specific relationship to any of them, a new genus is described, which is named Flexistipes, the flexible stick. Type species is Flexistipes sinusarabici strain MAS 10 (DSM 4947).     

The impact of medicinal brines on microbial biofilm formation on inhalation equipment surfaces

Abstract

Materials such as polyvinyl chloride, polypropylene, and polyethylene are used for the construction of medical equipment, including inhalation equipment. Inhalation equipment, because of the wet conditions and good oxygenation, constitutes a perfect environment for microbial biofilm formation. Biofilms may affect microbiological cleanliness of inhalation facilities and installations and promote the development of pathogenic bacteria. Microbial biofilms can form even in saline environments. Therefore, the aim of this study was to evaluate the effect of medicinal brines on microbial biofilm formation on the surfaces of inhalation equipment. The study confirmed the high risk of biofilm formation on surfaces used in inhalation equipment. Isolated microorganisms belonged to potential pathogens of the respiratory system, which can pose a health threat to hospital patients. The introduction of additional contaminants increased the amount of bacterial biofilm. On the other hand, the presence of brines significantly limited the amount of biofilm, thus eliminating the risk of infections.     

Oil removal and effects of spilled oil on active microbial communities in close to salt-saturation brines

Abiotic and biotic processes associated with the degradation of a light petroleum in brines close to the salt-saturation (~31 %) and the effect of labile organic matter (LOM) supply (casaminoacids/citrate; 0.2 and 0.1 % w/v, respectively) were followed during an incubation of 30 days. After 4-week incubation at 40 °C under light/dark cycles, a 24 % of abiotic degradation was observed in untreated brines. The stimulation of native brines community with LOM addition allowed an additional 12.8 % oil attenuation due to biodegradation processes. Successional changes in the active microbial community structure due to the oil contamination (16S rRNA DGGE approach) showed the selection of one phylotype affiliated to Salinibacter and the disappearance of Haloquadratum walsbyi in untreated brines. In LOM-amended microcosms, phylotypes related to Salinibacter, Haloarcula, Haloterrigena and Halorhabdus were selected. An effect of hydrocarbon contamination was only observed in the bacterial community with the inhibition of two dominant proteobacterial phylotypes. This study further confirms that short-term and moderate oil biodegradation is possible in LOM-stimulated brines. Biodegradation should be much more reduced under in situ conditions. Self-cleaning capacities of close to saturation hypersaline lakes appears, therefore very limited compared to non-extreme haline environments.     

The Wadi Natrun: Chemical composition and microbial mass developments in alkaline brines of Eutrophic Desert Lakes

Six lakes of the Wadi Natrun, Egypt, were studied with respect to the chemical composition of their brines and the occurrence of microbial mass developments. All investigated lakes showed pH values of approximately 11 and a total salt content of generally more than 30%. The main components were sulfate, carbonate, chloride, sodium, and minor amounts of potassium. Only traces of magnesium and calcium were present, but unusually high concentrations of organic carbon compounds, nitrogen compounds, and phosphate were found. Mass developments of phototrophic sulfur bacteria, halobacteria, cyanobacteria, and green algae were observed. The functions of complete nitrogen and sulfur cycles in the alkaline brines are discussed. The properties of the lakes and their ecology are compared with data on the Dead Sea and Great Salt Lake, Utah.     

Removal of uranium from solutions and brines by a derivative of chitosan and ascorbic acid

Dihydroxyethyltetrahydrofuryl chitosan (which is obtained from Euphausia superba chitosan upon Schiff reaction with dehydroascorbic acid and subsequent reduction of the ketimine obtained) can accumulate uranium from aqueous solutions, including 3% saline waters. By this chemical modification, the characteristic property of the chitosan-glucan complexes of fungal origin which collect uranium by chelation and hydrolysis is conferred to krill and shrimp chitosans. The capacity of dihydroxyethyltetrahydrofuryl chitosan is 1·0 g U/g and is about one order of magnitude higher than that of the cells of Rhizopus arrhizus and about two orders of magnitude higher than the mycelia of Penicillium digitatum.     

Biosurfactant-producing Bacillus are present in produced brines from Oklahoma oil reservoirs with a wide range of salinities

Nine wells producing from six different reservoirs with salinities ranging from 2.1% to 15.9% were surveyed for presence of surface-active compounds and biosurfactant-producing microbes. Degenerate primers were designed to detect the presence of the surfactin/lichenysin (srfA3/licA3) gene involved in lipopeptide biosurfactant production in members of Bacillus subtilis/licheniformis group and the rhlR gene involved in regulation of rhamnolipid production in pseudomonads. Polymerase chain reaction amplification, cloning, and sequencing confirmed the presence of the srfA3/licA3 genes in brines collected from all nine wells. The presence of B. subtilis/licheniformis strains was confirmed by sequencing two other genes commonly used for taxonomic identification of bacteria, gyrA (gyrase A) and the 16S rRNA gene. Neither rhlR nor 16S rRNA gene related to pseudomonads was detected in any of the brines. Intrinsic levels of surface-active compounds in brines were low or not detected, but biosurfactant production could be stimulated by nutrient addition. Supplementation with a known biosurfactant-producing Bacillus strain together with nutrients increased biosurfactant production. The genetic potential to produce lipopeptide biosurfactants (e.g., srfA3/licA3 gene) is prevalent, and nutrient addition stimulated biosurfactant production in brines from diverse reservoirs, suggesting that a biostimulation approach for biosurfactant-mediated oil recovery may be technically feasible.     

Aspartate glucan, glycine glucan, and serine glucan for the removal of cobalt and copper from solutions and brines

Aspartate glucan, glycine glucan, and serine glucan obtained by reductive amination of oxalacetic acid, glyoxylic acid, and beta-hydroxypyruvic acid, respectively, with polyglucosamine were tested as chromatographic chelating media. Crosslinked glycine glucan exhibited high capacities for cobalt and copper, even in acidic solutions (pH 2.9). Breakthrough points for 10 mg/L solutions through 6.0 x 0.6 cm columns containing 200 mg of polymer were at 1.8 L for both ions; for 1 mg/L solutions, they were at 4.0 and 12.0 L for cobalt and copper, respectively. Crosslinked glycine glucan could remove microgram amounts of cobalt and copper from fluoride and chloride brines. Cobalt and copper could be separated by elution with 0.25M sulfuric acid.